The cornea is a transparent membrane which bends or retracts the light to focus the light through the pupil
The second refraction occurs in the lens which help focus the image on the retina
The retina is light sensitive cells that lines the inside of your eyes it contains cells called rods and cones. Rods are sensitive and detect dim light while cones detect brighter light and colors
Answer:
1. Decibels
2. whisper - 20-decibels, normal talking - 60 decibels, rock concert - 120 decibels
3. 10,000
4. A Jet plane
Explanation:
1. The unit refers to what specifically is being measured. If the graph was of heights, it could be metres, centimetres, feet, or inches, for example. In this case, the graph is of sound level. We can see beside the Y axis label "Sound Level" that the unit is decibels.
2. Take each individual sound source and look at how tall the bars are (purple rectangles). For each one, we can look across to the Y axis (left side) and see the corresponding sound level for each
3. We were told in the introduction to the question that for every 10 decibel increase, the sound increases by 10 times. So going from 10 -> 20 decibels represents a 10x increase, and 10-> 30 represents a 100x increase.
To figure out the increase from whisper (20) to normal talking (60), take away 20 from 60 to see how many decibels difference there are between the two levels.
60-20 = 40
There is a 40 decibel increase. If 10 decibel difference = 10x and 20 decibel difference = 100x, then 30 = 1000x, and 40 = 10,000x (keep adding a 0 with every 10!)
4. We can see from the graph that the pain threshold is 120 decibels. The sound level that is greater than the pain threshold (meaning it would be painful) is the jet plane.
Cell membrane and the nuclear membrane
Answer:
B. Nucleus
Explanation:
The nucleus is a double membrane-bound structure responsible for controlling all cellular activities as well as a center for genetic materials, and it's transferring. It is one of the large cell organelles occupying 10% of total space in the cell.
Im pretty sure its a it took along time for the usa to form in its proper place and the ocean was always there and was always in contact with land